UCSF

Objective

To examine the association between sedentary behavior and blood pressure (BP) among Osteoarthritis Initiative (OAI) participants.

Design

We conducted a cross-sectional analysis of the OAI 48-month visit participants whose physical activity was measured using accelerometers. Participants were classified into four quartiles according to the percentage of wear time that was sedentary (<100 activity counts per min). Users of antihypertensive medications or non-steroidal anti-inflammatory drugs (NSAIDs) were excluded. Our main outcomes were systolic and diastolic blood pressures (SBP and DBP) and "elevated BP" defined as BP ≥ 130/85 mm Hg.

Results

For this study cohort (N = 707), mean BP was 121.4 ± 15.6/74.7 ± 9.5 mm Hg and 33% had elevated BP. SBP had a graded association with increased sedentary time (P for trend = 0.02). The most sedentary quartile had 4.26 mm Hg higher SBP (95% confidence interval (CI), 0.69-7.82; P = 0.02) than the least sedentary quartile, adjusting for age, moderate-to-vigorous (MV) physical activity, and other demographic and health factors. The probability of having elevated BP significantly increased in higher sedentary quartiles (P for trend = 0.046). There were no significant findings for DBP.

Conclusion

A strong graded association was demonstrated between sedentary behavior and increased SBP and elevated BP, independent of time spent in MV physical activity. Reducing daily sedentary time may lead to improvement in BP and reduction in cardiovascular risk.